Core catcher



UNITED s'rarlasf` PATENT'v OFFICE Jesse of Wright, Los Angeles,

Globe Oil Tools Co corporationof California A mpany.

Calif., assignor to Los Nietos, Calif., a

Applicatinnma'rch is, 1933, serial-N9'. 661,480

This inventionlrelatesto a core in a. well drilling tool or well-core drill, a general object' of the invention and effective in operation.

catcher for use and it is to provide a simple inexpensive core catcher that is dependable Another object of the invention is to provide a core catcher that embodiesonly two simple movable parts.

Another object ofthe invention isl'tozpr-ovide a core catcher that drill or-tool withoutv complicating the',

may be embodied in a core tool andV without increasing the wall thickness'or bulkv of any of the parts.

Another object of the invention is to provide a core catcher that may be carried directly in the bit head of the drill adjacent the cutting parts so that the drill may of maximum length.

be operable to obta in a core It is another object of the invention to provide a core catcher that does not embody springs or other parts subject to failure or distortion.

Another object of a core catcher that is the invention is to provide not liable to become mudded up or made inoperative by the presence of cuttings or debris.

A further object' of the invention is to provide a core catcher that includes two arcuate or substantially semi-circular members pivotally mounted in the core/,drill where they are adapted to surround the core and so that they are to swing downwardly and inwardly into engagement with the .core when the raised.

operable gripping drill is A further object of the invention is to provide a core catcher of the character mentioned that is extremely simple and inexpensive of manufacture and that is tion.

vpositive and eilective i typical forms and throughout which n opera- Other objects and features of the invention be more clearly understood from the following applicadescripis had to the accompanying draw-v lled secthe core provided by the gripping Fig. 2 ls a transverse detailed sectional view taken as indicated by line 2 2 on Fig. 1, showing gripping members in elevation. Fig. 3 is the core a central longitudinal detailed sectional view of the lower end portion of the core illustrating the c ore grip- `ping member, and Figui? u sectional viewv or an embodiment of .theinvenl0v ple, itmaybe employed `barreled core drills.

ping members in operativeengagement with the core. Fig. 4 isan enlargedplan elevation of one of the corev gripping members embodied in the formof the invention illustratedin Figs. 1, 2 and 3. Fig. 5, is a sideelevation .of the gripping meml 6 is a plan elevation of another form of core gripping member. Fig. 'l' is a plan elevation ofy another form ofcore gripis l a kvertical detailed tion involving gripping members of the type illus- Ytime in ng. "1.

{'I'he'c'ore catching means or core catcher provided :by the vpresent"invention, may be used in limited or restricted to the specific form or application about to'be described,l but is to be taken V25 as including any features or modifications that may fall within the scope of the claims. The curing outt or core drill illustrated in the drawing includes `a body 10 in the form of a barrel having a sub 11 screw-threaded on to its 30 lower end. The barrel or body 10 is adapted to be operated on the lower enel of a'string of drill pipe and may be connected with the drilling string in any suitable manner. In the particular form or application of the invention illustratedin the 35 drawing, a sub or connecting member 12 is provided on the sub 11 to carry the bit head 13. The

-subll has a pin 14 on its lower end screw-threaded into a socket 15 on the upper end of a member 12. 'I'he bit head includes a body 16 having a 40 socket 17 in its upper end. A tapered pin 18 on the lower end of the connecting member 12 is screw-threaded into the socket 17. 'I'he bit head body 16 is tubular and has a plurality of spaced 45 cutting blades projecting downwardly and outwardly from its lower end. The cutting blades 20 are operable to make an annular cut in the earth formation and provide a core that is passed upwardly 'through the opening '21 in the bit head 50 and received by the barrel l0. It is to be understood that the present invention may be used in connection with cre drills having various forms and types of cutters or cutting parts and is not to be considered as restricted -to use in a I will describe a typical embod- 20 A core drill having` cutters of the character illustrated in the drawing.

The core catching means or core catcher provided by the invention includes generally, a seat 22 in the body 16 of the bit head, and two pivoted corc gripping members 23 operable in the seat 22.

Theseat 22 is in the nature of an enlargement or recesain the opening 21 of the bit head. In accordance with the preferred form of the invention` the seat 22 is provided in the opening 21 at the lower end of the socket 17. The seat 22 is round in cross section and has a` spherically curved concave wall. The wall of the seat 22 is curved.

downwardly and inwardly as clearly illustrated in Figs. 1 and 3 of the drawing. Two diametrically opposite vertical or longitudinal grooves 24 are provided in the wall of the seat 22. The inner walls of the grooves 24 follow the curvature of the seat 22, that is, they are spherically curved downwardly and inwardly. The grooves 24 terminate at points spaced short distances above the lower end of the seat 22 and their lower ends form upwardly facing shoulders 25.

The body 16 of the bit head 13 illustrated in the drawing is comparatively short, and the seat 22 is located so that its lower end is only a short distance above the lower end of the body 16, it `being understood that the seat 22 may be located in the tool or core drill as found desirable or practical. Diametrically opposite grooves 26 are provided in the inner wall of the bit head body 16 at points 90 from the grooves 24. The grooves 26 extend downwardly into the seat 22 having their lower ends spaced below the upper end of the seat. If it is found desirable or necessary to make the grooves 26 of considerable depth, the grooves may extend upwardly in the threaded walls of the socket 17 to theupper end of the bit head body 16. It is to be notcdthat the formation of the seat 22 and the grooves 24 and 26 is simple and inexpensive and does not necessitate increasing the wall thickness of the body 16.

The core gripping members 23 are arcuate, being substantially semi-circular in plan elevation. The two members 23 are alike or complementary and are proportioned to operate or swing in the seats 22 and to pass the core when in their up or unactuated positions illustrated in Fig. 1. The peripheries or outer surfaces 27 of the core gripping members 23 may be spherically curved and may slidably engage the seat 22. In the pa'rticular case illustrated in the drawing, the outer surfaces 27 of the gripping members have suitable clearance with the wall of the seat 22. The upper ends of the arcuate gripping members 23 may be flat to effectively engage against the lower end of the pin 18 which overhangs the upper end of the seat 22. In accordance with the invention, the core gripping members 23 are separately or independently pivotally mounted in the bit head body 16 so that they are adapted to swing downwardly and inwardly in the seat 22.` Outwardly projecting lugs or trunnion projections 28 are provided on the opposite ends of each member 23. The trunnion projections on, the adjacent ends of the members 23 extend into the grooves 26. members 23 are positioned so that the projections 28 are disposed side by side on the lower ends of thevgrooves 26 as illustrated in Figs. 1 and 3 of the drawing. The trunnion projections 28 are round in cross section andare adapted to turn or bear in the grooves 26 to pivotally support the gripping members 23. The pin 18 removably retains the projections in the lower ends of the grooves 26 and upward movement of the trunnion Thel projections 28 is limited or prevented by the lower end of the pin 18. It is preferred to proportion and arrange the core gripping members 23 so that there may be suitable clearance between the adjacent trunnion projections 28 in the grooves 26.

Lugs or keys 30 are provided on the outer surfaces 27 of the core gripping members 23 to slidably operate in the grooves 24. The keys 30 are located midway between the ends of the gripping members 23 and their outer sides are curved to slidably engage the curved or concaved walls of the grooves 24. The keys 30 slidably cooperate with the key-ways 24 to effectively support the intermediate portions of the members 23 and to provide for suitable clearance between the outer surfaces 27 of the members and the seat 22. The cooperation of the keys 30 in the key ways or grooves 24 prevents turning or rotation of the gripping members 23 and prevents undesirable contact between the trunnion projections 28. When the core gripping members 23 pivot or swing downwardly and inwardly to the positions illustrated in Fig. 3 of the drawing, the keys 30 are adapted to engage the shdulders to limit the downward and inward motern'ent of the gripping members. It is preferred to make the keys comparatively short and to position them adjacent the upper ends of the gripping members 23 to allow for maximum movement of the members.

CoreY gripping parts or teeth 32 are provided in the inner sides of the members 23. The teeth 32 may be suitably shaped to effectively bite into the core when the members 23 are swung downwardly and inwardly into engagement with the core. In the particular form ofthe invention illustrated in Figs. 1 to 5 of the drawing, the gripping teeth 32 extend the entire lengths of the members 23. The lowerends or edges of the core gripping members 23 may be inclined downwardly and circumferentially from theopposite ends of the members. Fig. 6 of the drawing illustrates a form of core gripping member 23e provided with gripping teeth 40 spaced midway between its ends. The core gripping teeth 40 may be shaped similar to the teeth 32 and are of suitable length. The teeth 40 of the pair of members 23 in being located between the opposite ends of the members are adapted to effectively grip diametrically opposite portions of the core when the members are actuated. Further, the vteeth 40 are positioned directly inward of the keys 30a so that the keys are operable to transmit the greater part of the thrusts and weight of the core directly to the body of the tool, thus relieving the trunnion projections 28a at the ends of the members.

'In assembling the tool, the trunnion projections 28 of the members 243are passed into the grooves 26 and the members are lowered or dropped through the socket 17 to allow the projections 28 to seat or bear on the lower ends of the grooves. The pin 18 of the sub or connecting member 12 may then be threaded into the socket 17 to attach the bithead 13 to the sub and to retain the core gripping members 23 in position. It will be apparent how the core gripping members 23 may be readily removed for replacement or the like, by threading the pinl 18 out of the socket 1'7 so that the projections 28may be passed upwardly through the grooves 26. During the drilling operation, that lis,when the drill is rotated to cut a core, the core passing upwardly into VVthe drill holds the gripping members 23 in the up or'inoperative positions illustrated in Fig. l of the drawing. When it is desired to remove the drill and to break the core loose from the earth formation, the drill is raised or pulled upwardly. When the drill is raised the weight of the members 23 and the engagement of the members v23 with the stationary core, causes the members to pivot or swing downwardly and inwardly in the seat 22. This downward and inward swinging of the members 23 relative to the bit head 13 brings the members into gripping engagement with the core. It will be apparent how continued upward movement of the drill causes the members 23 to swing to their fully actuated position illustrated in Fig. 3 of the drawing where the keys 30 engage the stop shoulders 25 to limit further downward swinging of the members.

When the gripping members 23 are in the positions illustrated in Fig. 3 they obtain a firm positive gripping and 'supporting engagement with the core so that the core is broken away from the formation and is retained in the drill when it is withdrawn from the well.

It is to be noted that the keys 30 in slidably fit-ting the grooves 24 effectively support the members 23 with a minimum amount of friction during their actuation or swinging movement, and engage the shoulders 25 and the walls of the grooves 24 when the members are fully actuated to transmit the greater portions of the load directly to the bit head body 18, thus relieving strains on the trunnioniprojections 28. The core catching means of the present invention is extremely simple and inexpensive of manufacture, and is positive and dependable in operation. The gripping members 23 are simplesturdy parts l and are not liable to become inoperative by accumulations of cuttingsor the like. The core catcher does not materially complicate the drill,

and does not necessitate the provision of h/eavy or thickwalled parts in the drill. The members 23 in individually swinging downward and inward obtain firm grips `or holds on diametrically opposite sides of the core'and are thus effective in supporting the core in the drill.

The embodiment of the invention illustrated in Figs. 'l and 8 of the drawing includes, generally, a seat in the bit head body or shoe 51, and two pivoted gripping members 52 operable in the seat 50. The seat 50 is in the core receiving opening of the bit head shoe 51 at thelower end of a screw threaded socket 53, The walls of the seat 50 are spherically curved downwardly and inwardly, and the seat is of round horizontal cross section. Two diametrically opposite notches l or grooves 54 are provided in the upper portion of the seat 50. If found desirable or necessary, the grooves 54 may extend upwardly in the threaded walls of the socket 53 to the upper end of the shoe 51. The seat 50 terminates at its lower end in an upwardly facing annular shoulder 55. The shoulder .55 may be inclined downwardly and inwardly as illustrated. The threaded pin 56 of a sub, or the like, is threaded into the socket 53, and its lower end presents a'downwardly facing shoulder on the upper end of theseat. The core gripping members'52 are similar generally, to the members 23 described above, that is, they are substantially semi-circulararfd are provided at their opposite ends with pivot or; trunnion projections 58.- ,The projections58 are round in cross section and bear or'seat on the` lower end walls of the grooves54. The lower end of the pin 56 retains the projections-58 in-their proper positions 1in the grooves.. The gripping members 52 are arranged in end to end relation in the seat 50-and are provided withjouter 'or peripheral surfaces 59V sphericallycurved to slidably bear on or cooperate with the walls of the seat. The bearing surfaces 59 maybe continuous throughout the lengths of the gripping members. Downwardly and inwardly inclined peripheral surfaces 60 are provided on -the core gripping members 52 below' ther bearing surfaces 59. The surfaces 59 slidably cooperate with the walls of the ,seat 50 so that the gripping members 52 are operable to swing or pivot on the seat. Core gripping parts or teeth 61 are provided on the inner sides of the core gripping members 52. The teeth 6l may be similar to the teeth 32 de` scribed above.

'Ihe operation of the embodiment of the inven-y tion illustrated in Figs. 7 and 8. is similar to that of the other forms of the invention. During the d held in their up or inactive position againstA the lower end of the pin 56 by the core. Whe'n the drill is raised to break the core loose from the formation, the relative movement between the drill and the core causes the gripping members 52 to pivot orv swing downwardly on the seat 50.- This. downward swinging of the ygripping members 52 brings their teeth into rm lgripping engagement with the core. 'I'he inclined surfaces 60 of the gripping members are adapted to cooperate with the shoulder to limit the downward swinging of the members and the shoulder 55, together with the walls of vthe seat 50, carry the gripping members so that the core is directly supported on th'ebit head shoe 5l. The peripheral surface 59` of the gripping members bear on the wa'tls of the seat 50 so that the load or weight of the core is not entirely carried .by the projections 58. The shoulder 55 may be located immediately vadjacent the lower end of the core receiving opening of the bit head sothat the gripping members 52 are operable to project substantial distances into the opening and grip the core at points immediately'adjacent the cutting parts of the bit head.

Having described only typical preferred forms and applications of my invention, I do net wish to limit or restrict myself to the specific forms or applications above set forth, but wish to reserve to myself any variations or modifications that may appear to those skilled in the art or fall within the vscope of the following claims: Having described my invention, I claim: 1. Core catching 'means for use in a. drill having an opening for receiving a core which includes, two arcuate members arranged with their ends opposing one another, `means pivotally mounting the end parts of the'members on the wall of the body so that the members are movable downwardly and inwardly into gripping engagement with the core, and means slidably supporting vthe members at points betweenr their ends during such movement.

2,.-A core drill including, a body having an jope'ningjfor receiving a corefc'utting vmeans rig. 'idly secured to the .lower end Vof the body, two

substantially semi-circular members arranged in the opening in end to end relation, there being two spaced recessesin vthe wall of the opening,

and projections on they members adjacent their,

ends bearingin rthe recesses whereby the membersl are operable to swing inwardly .toward yone another` into gripping engagement with the core.

3. A'core drill including, a body having an openingfor receiving a core, cutting means on thebody, two substantially semi-circular members normally concentrically disposed in the open- 'l ing, means pivotally supporting the members in the body so that theymay swing downwardly and toward one another when the body is raised, and key and groove connections slidably supporting the members on the body at points between th ends of the members.

4. A core drill including, a body having an opening for receiving a core, cutting means on the body, there being a spherically curved concave ,seat in the opening, and two substantially semi-circular core gripping members pivotally mounted in the opening to swing downwardly on said seat when the body is raised, the members bearing on the wall of the body between their pivotal axes during such swinging movement.

5. A core drill including, a body having an opening for receiving a core, cutting means on the body, there being a spherically curved concave seat in the opening and spaced recesses in the wall of the seat, two substantially semi-circular core gripping members in the opening at the seat, and projections on the end parts of the members cooperating with the recesses to pivotally support the members; whereby they may swing downwardly on the seat, the members bearing on the wall of the body between their pivotal axes during such swinging movement.

6. A core drill including, a body having an opening for receiving a core, cutting means on the body, there being a spherically curved concave seat in the opening and spaced recesses in the wall of the seat, two 'substantially semi-circular core gripping members in the opening at the t, core gripping teeth on the inner sides of the members, and projections on the end parts of the members cooperating with the recesses to pivotally support themembers whereby they may swing downwardly on the seat, the members bearing on the wall of the body between their pivotal axes during such swinging movement.

'7. A core drill including, `a body having an opening for receiving a core, cutting means on the body, there being a spherically curved `concave seat in the opening andl spaced recesses in the wall of the seat, two substantially semicircular core gripping lmembersin the opening at the seat, projections on the members cooperating with the recesses to pivotally support the members whereby they may swing downwardly on the seat, there being grooves in the wall of the seat, and keys on the members slidable in said grooves.

8. A core drill including, a body having an opening for receiving a core, cutting means on the body, there being a spherically curved concave seat in the opening and spaced recesses in the wall of the seat, two substantially semicircular core gripping members in the opening at the seat, projections on the members cooperating with the recesses to pivotally support the members whereby they may swing downwardly on the seat, there being grooves inthe wall of the seat, upwardly facing shoulders at the lower ends of the grooves, and keys on Ithe members slidable in said grooves, and adapted to cooperate with the shoulders to limit downward movement of the members.

9. In a core drill, a body having an opening for receiving a core and a socket inthe upper end of the opening, cutting parts on the body for making an annular cut, there being two spaced recesses in the opening at the lower end of the socket, two curved members in the opening in end to end`relation, projections on the end portions of the members cooperating with the recesses to pivotally support the members whereby they may swing downwardly to grip the core, and a part having a pin threaded in the socket to retainy the projections in the recesses, the lower end of the pin forming a shoulder to limit upward swinging of the members.

10. A core drill including, va body having an opening for receiving a core, means on the body for making an annular cut, there being a curved concave seat in the opening, and two substantially semi-circular members pivotally mounted in the body. and having their outer sides slidably bearing on the seat whereby the members are movable downwardly and inwardly on the seat into gripping engagement with a core in the opening.

JESSE C. WRIGHT. 

